How to keep stream open?

zhshqzyc

We all know write a string to a file is simple. Such as:

1. 
   
2. import java.io.*;
   
3. class FileWrite
   
4. {
   
5.    public static void main(String args[])
   
6.   {
   
7.       try{
   
8.     // Create file
   
9.     FileWriter fstream = new FileWriter("out.txt");
   
10.         BufferedWriter out = new BufferedWriter(fstream);
    
11.     out.write("Hello Java");
    
12.     //Close the output stream
    
13.     out.close();
    
14.     }catch (Exception e){//Catch exception if any
    
15.       System.err.println("Error: " + e.getMessage());
    
16.     }
    
17.   }
    
18. }
    

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I have a case which needs write strings in many methods.
How can I pass file name or stream and implement it?
(Open the stream, pass the stream into each method)

1. 
   
2. public void doDiff(String oldFile, String newFile, String Directory) {
   
3.       
   
4.     String path = System.getProperty("user.dir");
   
5.     String DiffFileName = path+'/'+Directory+'/'+ oldFile+"D.txt";
   
6.    
   
7.     File file = new File(Directory,DiffFileName);
   
8.     try{
   
9.             FileWriter outFile = new FileWriter(file);
   
10.             BufferedWriter out = new BufferedWriter(outFile);
    
11.             String s1 =  ">>>> Difference of file \"" + oldFile  
    
12.             +  "\" and file \"" + newFile + "\".\n";
    
13.             out.write(s1);
    
14.             out.flush();
    
15.     }
    
16.     catch (Exception e){//Catch exception if any
    
17.             System.err.println("Error: " + e.getMessage());
    
18.     }
    
19. showinsert(file)
    
20. }
    
21. void showinsert(File file)
    
22.   {
    
23.        if ( printstatus == change ) println( ">>>>     CHANGED TO" );
    
24.        else if ( printstatus != insert )
    
25.       String sn= ">>>> INSERT BEFORE " + printoldline ;
    
26.   // how can I print sn into file
    
27. // do I need to create stream again?
    
28.        printstatus = insert;
    
29.        newinfo.symbol[ printnewline ].showSymbol();
    
30.        anyprinted = true;
    
31.        printnewline++;
    
32.   }
    

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